Special educators and clinical professionals who serve individuals with developmental disabilities such as mental retardation or autism routinely rely on behavioral observation for critical information. This STTR application seeks funds to support the development of the Praxis Behavioral Observation Software (PBOS), a tool to enhance the efficiency and accuracy of behavioral observation with the widely used measurement techniques of partial/whole interval recording and momentary time sampling. These techniques are used in situations where practical considerations prohibit continued direct observation and recording every instance of behavior. With these measurement techniques, the total observation period is divided into smaller intervals and some portion of each interval is observed. The software will perform 2 types of functions: (1) Improve the efficiency of coding digital video behavioral samples. Continuously recorded digital video can be automatically divided into a series of user-defined video segments and each segment automatically displayed based on the needs of the user. Efficiency will be improved because the user does not need to view the entire video sample, but rather only the portions that are necessary for coding. (2) PBOS can be used to determine the relative accuracy of different measurement techniques. The user will first code a representative sample of the behavior by viewing an entire digital video while recording behavioral events. This produces a complete record of the actual frequency and duration of the behavior. The software will then calculate the estimated frequency and duration of this behavior that would be obtained using a range of momentary time sampling and interval recording values. The software will display the extent to which each set of recording parameters over-or under-estimates the actual frequency and duration of the behavior and indicate which coding strategy best measures the specific characteristics of the behavior of interest. The software development process will include implementation of the coding and analysis modules, verification of accuracy through comprehensive in-house testing, field tests for usability and clarity of user interface and documentation, and 2 product revision cycles. Special educators and clinical professionals who serve individuals with developmental disabilities such as mental retardation or autism are increasingly using digital video for behavioral observation and analysis. The Praxis Behavioral Observation Software (PBOS) product will include features to increase the accuracy and efficiency of conducting such analyses. Further, the product will include tools to determine the most accurate behavioral measurement techniques for analyzing digital video samples and conducting direct (live) behavioral observation. [unreadable] [unreadable] [unreadable]